Commit e5554e20 authored by Stratos Psomadakis's avatar Stratos Psomadakis Committed by Luiz Capitulino
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monitor: Reset HMP mon->rs in CHR_EVENT_OPEN 



Commit cdaa86a5 ("Add G_IO_HUP handler for socket chardev") exposed a bug in
the way the HMP monitor handles its command buffer. When a client closes the
connection to the monitor, tcp_chr_read() will detect the G_IO_HUP condition
and call tcp_chr_disconnect() to close the server-side connection too. Due to
the fact that monitor reads 1 byte at a time (for each tcp_chr_read()), the
monitor readline state / buffers might contain junk (i.e. a half-finished
command). Thus, without calling readline_restart() on mon->rs in
CHR_EVENT_OPEN, future HMP commands will fail.

Signed-off-by: default avatarStratos Psomadakis <psomas@grnet.gr>
Signed-off-by: default avatarDimitris Aragiorgis <dimara@grnet.gr>
Signed-off-by: default avatarLuiz Capitulino <lcapitulino@redhat.com>
parent 81ab11a7

monitor.c

+1 −0
Original line number Diff line number Diff line
@@ -5249,6 +5249,7 @@ static void monitor_event(void *opaque, int event) 
        monitor_printf(mon, "QEMU %s monitor - type 'help' for more "

                       "information\n", QEMU_VERSION);

        if (!mon->mux_out) {

            readline_restart(mon->rs);

            readline_show_prompt(mon->rs);

        }

        mon->reset_seen = 1;